There are batteries of a type that comprises an electrode stacked body including a plurality of electrodes and separators each being put between adjacent two of the separators, and a pair of laminate films that constitute a package to hermetically put therein the electrode stacked body. In such batteries, when the electrode stacked body is forced to move in the package of the laminate films due to a shock or the like, malfunction of the battery tends to occur. Thus, it is desirable to suppress undesirable movement of the electrode stacked body in the laminate film package.
In the technique disclosed by Patent Document 1, at least one of the separators is shaped flat and has a size larger than the other separators and electrodes that constitute the electrode stacked body, and a part of the flat and larger separator projects outward from a side of the electrode stacked body. The part of the flat and larger separator that projects outward from the electrode stacked body is put between respective peripheral portions of a pair of laminate films. That is, between the peripheral portions of the paired laminate films, there is inserted the part (or projected part) of the flat and larger separator, and at the time when the peripheral portions of the paired laminate films are joined via heat joining or the like, the projected part of the flat and larger separator, which is put between the peripheral portions of the paired laminate films, is also joined to the peripheral portions, so that the electrode stacked body is stably set in the laminate film package.
In the technique disclosed by Patent Document 2, the electrodes and separators are alternately stacked on one laminate film, and each time an electrode or separator is stacked, a tab film bonded to the electrode or separator by itself is joined to the laminate film via heat joining or the like. Finally, another laminate film is put on the stacked body, and peripheral portions of the two laminate films are joined via heat joining or the like. Also by this technique, the tab films and separators that are bonded to the electrodes are respectively joined to the paired laminate films, and thus, undesirable movement of the electrode stacked body in the passage is suppressed.